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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 1:41 am 


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Joined: 25 Mar 2009
Posts: 292
Location: USA
MarkOZLAD wrote:
Now I’m confused about which models we are discussing.


Sorry for the confusion. I was talking about the Sharp. The "ix2933ce" is really just a toshiba ta1268n jungle. Sharp likes to rename chips sometimes...for some reason.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 3:26 am 



Joined: 20 May 2020
Posts: 17
matt wrote:
MarkOZLAD wrote:
The inlines in the RGB lines are 6800 Ohm so the mux resistors are 1100 ohm (1000 ohm would likely be fine).

So send 75 ohm terminated RGB lines into 1100 ohm resistors and then connect to the RGB circuits. The legs of R2024, R2025 and R2026 farthest from micro controller might be good spots to attach wires.

For blanking use the 8 Bit Guy RGB mod part 2 method. Lift the leg of R2027 that is closest to the micro controller and inject 5V into it.


I did an RGB mod to a 13K-M100 a while back. 1k ohm resistors worked well.

RGB on this TV is very dark with 75 ohm termination (I think I remember reading that this jungle IC expects 1v p-p). In my case I was able to get a satisfactory picture by adjusting the flyback pot and the RGB cutoffs in the service menu, but there may be a better way to deal with this.


I'm a little lost with this mod, actually. I thought it was going to be a breeze, but I guess I'm not the best at knowing how to connect things on a pcb. I'm not able to see an OSD or a game at all.

I removed the old, 1.8kO terminating resistors, but I don't want to hook anything up to their old pads (small SMD --seems difficult), so I need to relocate them. Where should I ground them? Right now I have them going to a ground point on an unused connector towards the RF module. And I thought I found 5V on IC2101 but I'm not sure that it's actually... working? Here's a rough sketch of how I have things set up.

Spoiler: show
Image


The "ext" triangle-looking section is where I'm pretty sure that I'm messing things up. I'm hooking up the mux resistor (currently 1.1kO) directly to the leg of the inline resistors that points towards and connects to the jungle chip. The terminating resisotrs are coming off of this triangle and going to ground.... I guess they're not even in line with the original resistors any more...

Any insight would be great. I feel pretty close.


Last edited by zFleeman on Mon Sep 14, 2020 8:02 pm, edited 1 time in total.

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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 8:16 am 



Joined: 18 May 2017
Posts: 755
zFleeman Looks right to me.
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MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 7:30 pm 


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Joined: 09 May 2005
Posts: 229
Location: Honolulu, Hawaii
MarkOZLAD wrote:
1.0Vp-p RGB huh? Very interesting.

I wonder if the termination resistor should be changed to 180 ohm. That should give 1.0Vp-p from external RGB.

Would then use 1600 ohm mux resistors.


Don't trust me on the 1vpp thing. I can't remember where I read it (possibly somewhere buried in this thread) and wasn't able to find a good enough datasheet to verify it.

The picture does indeed improve with higher value terminating resistors. However, I was under the impression that 75 ohms was needed for signal quality from the console side. Am I wrong?

cyborc wrote:
MarkOZLAD wrote:
Now I’m confused about which models we are discussing.


Sorry for the confusion. I was talking about the Sharp. The "ix2933ce" is really just a toshiba ta1268n jungle. Sharp likes to rename chips sometimes...for some reason.


I believe you're mistaken here. The Sharp IC has a different pinout from the ta1268n (blanking is on pin 17 vs 14 on the Toshiba chip). I'd thought that it was a rebranded Sanyo chip.

Around the same time I experimented on an RGB mod on a Sanyo DS13320, which uses an LA76834NMP jungle. It behaved the same as the Sharp, although the TV had other problems and I ended up discarding it.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 7:42 pm 


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Location: Honolulu, Hawaii
zFleeman wrote:
I'm a little lost with this mod, actually. I thought it was going to be a breeze, but I guess I'm not the best at knowing how to connect things on a pcb. I'm not able to see an OSD or a game at all.

I removed the old, 1.8kO terminating resistors, but I don't want to hook anything up to their old pads (small SMD --seems difficult), so I need to relocate them. Where should I ground them? Right now I have them going to a ground point on an unused connector towards the RF module. And I thought I found 5V on IC2101 but I'm not sure that it's actually... working? Here's a rough sketch of how I have things set up.


Your schematic looks correct to me, if you're getting nothing it's likely that something is connected wrong.

Have you tested your blanking with a composite signal? For me this is usually the first step.

I usually just put my terminating resistors on the RGB connector. Soldering to those SMD pads is a pain.

IIRC I used pin 1 of the 5v regulator (IC101) for blanking.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 11:08 pm 


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Posts: 292
Location: USA
matt wrote:


I believe you're mistaken here. The Sharp IC has a different pinout from the ta1268n (blanking is on pin 17 vs 14 on the Toshiba chip). I'd thought that it was a rebranded Sanyo chip.

Around the same time I experimented on an RGB mod on a Sanyo DS13320, which uses an LA76834NMP jungle. It behaved the same as the Sharp, although the TV had other problems and I ended up discarding it.


Unless there are different versions of the 13k-m100, the service manual even states that ic201 is a toshiba ta1268n.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 29, 2020 11:47 pm 


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Location: Honolulu, Hawaii
cyborc wrote:
Unless there are different versions of the 13k-m100, the service manual even states that ic201 is a toshiba ta1268n.


You are correct. Sorry, I must have gotten my datasheets mixed up!


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 5:58 am 



Joined: 22 Aug 2017
Posts: 6
Sup everyone, I'm trying to enable the component output on this TV (Philips 19ST200L17) but I'm having some trouble getting it working.

Here's the datasheet:

https://www.dropbox.com/s/5evc4ohuvja10 ... 3.pdf?dl=0

I checked out the datasheet and noticed the chip supports component but the TV doesn't have the connectors. I went into the service mode and turned the component video on, and I can switch to it via the remote. So far what I've done is soldered leads to where the connector would be on the board, but that gets me no video and when I connect a component source along with a composite or svideo source simultaneously, the TV goes off. When I use connections further down the circuit I do get working component video on that input but it's distorted somewhat (washed out colors, warping and discoloration), I tested the lines for DC and each line has 13v running through it.

Datasheet for the IC:

https://www.dropbox.com/s/h3q3zmsgs5lpl ... X.pdf?dl=0

I'm not great with electronics, I have modded a couple TVs and I work on guitar tube amps but that's been very simple soldering and such. I don't understand circuits too well so this is having me scratching my head a bit...


Last edited by snappleman on Sun Aug 30, 2020 7:18 am, edited 2 times in total.

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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 5:59 am 



Joined: 18 May 2017
Posts: 755
matt wrote:
cyborc wrote:
Unless there are different versions of the 13k-m100, the service manual even states that ic201 is a toshiba ta1268n.


You are correct. Sorry, I must have gotten my datasheets mixed up!


In my experience with that family of chips I’d say you will be fine with either 0.7Vp-p or 0.5Vp-p patterns.
_________________
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MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 3:26 pm 


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Joined: 26 May 2015
Posts: 99
Location: Florida
snappleman wrote:
Sup everyone, I'm trying to enable the component output on this TV (Philips 19ST200L17) but I'm having some trouble getting it working.

Here's the datasheet:

https://www.dropbox.com/s/5evc4ohuvja10 ... 3.pdf?dl=0

I checked out the datasheet and noticed the chip supports component but the TV doesn't have the connectors. I went into the service mode and turned the component video on, and I can switch to it via the remote. So far what I've done is soldered leads to where the connector would be on the board, but that gets me no video and when I connect a component source along with a composite or svideo source simultaneously, the TV goes off. When I use connections further down the circuit I do get working component video on that input but it's distorted somewhat (washed out colors, warping and discoloration), I tested the lines for DC and each line has 13v running through it.

Datasheet for the IC:

https://www.dropbox.com/s/h3q3zmsgs5lpl ... X.pdf?dl=0

I'm not great with electronics, I have modded a couple TVs and I work on guitar tube amps but that's been very simple soldering and such. I don't understand circuits too well so this is having me scratching my head a bit...


I modded a Philips tv a few years ago with component.

Did you add 0.1 caps and 75ohm resisters?


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 5:22 pm 



Joined: 22 Aug 2017
Posts: 6
Pikkon wrote:

I modded a Philips tv a few years ago with component.

Did you add 0.1 caps and 75ohm resisters?


Resistors yes, caps no... I'll go and do that today and see if it works.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 9:20 pm 



Joined: 16 Aug 2020
Posts: 7
MarkOZLAD wrote:
Shiozaki wrote:

tiny surface mount, I guess I could try and tombstone some components on purpose, IDK, any input is always welcome.

https://imgur.com/a/scTNXie


Surface mount makes it a pain but all the same concepts apply are there any jumpers on the RGB circuits lines that could provide an easy in?


This is what I've come up with, tell me itll work lol.
I removed the surface mount 534 535 536 and 537 and just grounded it at the connector with the 75R's.
https://imgur.com/a/KPw6tB9


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 30, 2020 11:37 pm 



Joined: 22 Aug 2017
Posts: 6
snappleman wrote:
Pikkon wrote:

I modded a Philips tv a few years ago with component.

Did you add 0.1 caps and 75ohm resisters?


Resistors yes, caps no... I'll go and do that today and see if it works.


Just got around to it, adding the caps didn't work. The picture goes dark and scrambled as if it lost sync:

Image

When I take out the caps it looks "better" but with this strange discoloration pattern:

Image

Like I said before I'm connecting the signal to V1/V2/V3 on the chassis:

Image

Anywhere before that gives me no picture. But I'm not planning on messing about any farther until I do some reading up on this and maybe get some guidance from here.


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 31, 2020 4:45 am 



Joined: 22 Aug 2017
Posts: 6
Sorry for the barrage of posts everyone, but I read up a bit and looked through the schematics and got the component video working by soldering to the ITV unit instead of the unpopulated connectors.

I also searched this topic and found some stuff MarkOZLAD said about another TV with this chip in it, and he suggested getting RGB by switching to the composite AV input that the component line is connected to, I hooked up RGBS(sync on composite) to the component connector I made and then went into the service menu and disabled component video input, and turns out MarkOZLAD was right! RGB on AV input, but I can only switch to it by going into service, enabling component video, switching to component input, disabling component input and switching to AV, so I assume I will have to add a switch that sends 1-3v to blanking as suggested and maybe I can add a SCART connector as well and switch between component and RGB as needed? So thanks for the retroactive help!


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 31, 2020 5:05 am 



Joined: 18 May 2017
Posts: 755
Shiozaki wrote:
MarkOZLAD wrote:
Shiozaki wrote:

tiny surface mount, I guess I could try and tombstone some components on purpose, IDK, any input is always welcome.

https://imgur.com/a/scTNXie


Surface mount makes it a pain but all the same concepts apply are there any jumpers on the RGB circuits lines that could provide an easy in?


This is what I've come up with, tell me itll work lol.
I removed the surface mount 534 535 536 and 537 and just grounded it at the connector with the 75R's.
https://imgur.com/a/KPw6tB9


That looks right.
_________________
___________________________________________________
MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 31, 2020 3:55 pm 



Joined: 20 May 2020
Posts: 17
Sharp 13-KM100 Results

I got everything to work just fine with the 75ohm terminator and 1100ohm mux. Thank you for the help, everyone! I had to put this onto a breadboard to better visualize what I was doing incorrectly. I didn't have the terminating resistor in the right spot. Now I'm going to upgrade its caps and put it all back together.

Image
Image
Image

zFleeman wrote:
Another wrinkle in this situation: The RGB lines do not have any resistors between them and ground. The blanking grounding resistor has a value of 2.17kO.

So, in summary, here are the differences with this board (SB314) that I'm noticing. Let me know if they change this mod from SB315.
  • Inline resistor for blanking is a diode, not a resistor. Can this be replaced with a 180 ohm like in Syntax's schematic?
  • The only grounding resistor present on the board was a 2.17kO resistor. This seems like it was different from arithmaldor's. Are the empty resistor slots still okay to be terminated with a 75 ohm and combined with a 360 ohm for my external RGB lines?


And if it wouldn't be too much trouble, I was wondering if I could get some help on this spongebob mod. I can't find a schematic for the SB314 anywhere, but the inline resistors for the RGB lines [i]were[/] 1kO before I swapped everything to match this image, and there's a diode on the blanking inline (which is now a 180ohm). I've quoted some of the other concerns I have with this mod. I know I'll probably have to go back to square one with this fella, but that's fine by me!


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 6:05 am 



Joined: 02 Sep 2020
Posts: 1
Hello; so, this isn't a post addressed to a specific model TV, but I see that most if not all RGB mods that preserve the OSD attach the RGB input directly to the bus going from the microcontroller to the jungle IC, which seems to have the effect of blending the OSD and inputted image together when the OSD is active.

Has anyone ever attempted using a multiple channel, 2:1 multiplexer and wiring the blanking output of the microcontroller to the select pin of the multiplexer? That way, the OSD won't be blended in with the image, but will completely "cover" it as it does normally.

I don't know if that's making any sense; I drew a schematic for what I'm trying to describe, but it doesn't look like this forum supports attachments?


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 2:00 pm 


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Posts: 84
Sony KV-20M10
CXA1465AS Jungle IC

Had to desolder the unused Analog RGB inputs (16, 17, 18), which were all tied together to ground:

Spoiler: show
Image


Cleaned up with desoldering braid and used a meter to make sure none of them were touching anything they shouldn't be anymore. Then I made a 1k/1k voltage divider to pull the 9V Vcc on Pin 2 of the jungle down to 4.5V to use for blanking. I connected R. G, and B via 75 ohm terminated connections with 0.1u caps to the newly desoldered pins, connected sync to the Composite Video input, applied the 4.5V to Ys (Pin 15) on the jungle IC, and:

Spoiler: show
Image


Textbook. OSD is intact due to the built-in mixing functionality of the jungle. I was worried about the unused inputs being disabled via I2C, especially since other sets with this same jungle IC are, but I got lucky here.


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 8:18 pm 



Joined: 20 May 2020
Posts: 17
I'm looking at picking up a Sanyo DS19330 from somebody on Craigslist, and I'm seeing some promising things on page 28 of this manual. Does this mod look simple? I've searched around this forum and saw that this person tried it on a similar set a while ago -- looks like they didn't get too far. Also, how can I know if this one is digital vs analog rgb? That also seems to be a toss-up on this tv.

I looked at Mark's 0.7v table would indicate that I would use 910ohm on the external lines with 75ohm terminating?

Out
Spoiler: show
Image


In
Spoiler: show
Image


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 8:54 pm 


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zFleeman wrote:
I'm looking at picking up a Sanyo DS19330 from somebody on Craigslist, and I'm seeing some promising things on page 28 of this manual. Does this mod look simple? I've searched around this forum and saw that this person tried it on a similar set a while ago -- looks like they didn't get too far. Also, how can I know if this one is digital vs analog rgb? That also seems to be a toss-up on this tv.

I looked at Mark's 0.7v table would indicate that I would use 910ohm on the external lines with 75ohm terminating?


That looks right. Remove R842, R843, and R844 and do your injection there.


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 9:19 pm 



Joined: 20 May 2020
Posts: 17
Osirus wrote:

That looks right. Remove R842, R843, and R844 and do your injection there.


Sounds promising. But before I commit to driving out to get this set -- I'm having a hard time understanding what this person was going through with the smaller version of this TV. How can I find out if the RGB lines are digital or not? The chip they were trying to put RGB into was an LA76843 and mine is a LA76834.


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Sep 02, 2020 9:24 pm 


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Posts: 84
zFleeman wrote:
Osirus wrote:

That looks right. Remove R842, R843, and R844 and do your injection there.


Sounds promising. But before I commit to driving out to get this set -- I'm having a hard time understanding what this person was going through with the smaller version of this TV. How can I find out if the RGB lines are digital or not? The chip they were trying to put RGB into was an LA76843 and mine is a LA76834.


I can't find a datasheet for that IC, but the schematic has a voltage divider in the OSD lines with 5.6k ohm inline and 860 ohm ground, assuming 5V out of the microcontroller this leaves 0.7V going into the jungle, which is a strong indicator of standard analog RGB.


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Sep 03, 2020 1:51 am 


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Posts: 22
Location: Salem, NH
Total novice here, looking for advice.

I want to turn my KD-34XBR960 into a 1080i/540p VGA monitor.
I hope to inject 33.75Khz RGBHV in place of the OSD; bypassing the labyrinth of digital processing ICs this set uses.
I'm not concerned with preserving any of the set's original inputs/functionality.

I think I've sniffed out the right location, but I have no idea where to start.



What does YSYM mean? Is it blanking?

What kind of components would I need between my VGA source and these OSD connections?



The following was taking from the official service manual for this set:
("CX" is the video-out board that plugs directly into the base of the tube)


Here's the Block Diagram from the Service Manual -
Spoiler: show
Image


Here's the CRT Drive Schematic -
Spoiler: show
Image


Much Thanks :mrgreen:


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Sep 03, 2020 7:28 pm 



Joined: 20 May 2020
Posts: 17
I just got the Sanyo DS19330 home, and I'll start work on it tomorrow. I was looking at the schematic, and I had the unfortunate realization that the current grounding resistors and inline resistors are surface mount. I'm really really not looking forward to messing with such tiny parts -- I was wondering if anybody has any tips or products that I should order that help with soldering wires onto surface mount leads. I'm anticipating a lot of hot glue usage in my near future.

Components:
Image

Geometry on Composite -- Good!:
Image


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Sep 03, 2020 8:50 pm 


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Posts: 292
Location: USA
zFleeman wrote:
I just got the Sanyo DS19330 home, and I'll start work on it tomorrow. I was looking at the schematic, and I had the unfortunate realization that the current grounding resistors and inline resistors are surface mount. I'm really really not looking forward to messing with such tiny parts -- I was wondering if anybody has any tips or products that I should order that help with soldering wires onto surface mount leads. I'm anticipating a lot of hot glue usage in my near future.


according to the service manual, this tv is hot chassis. so if you are planning to add rgb inputs to it, it must always be plugged into an isolation transformer going forward.

https://www.manualslib.com/manual/69976 ... e=4#manual


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Sep 03, 2020 9:18 pm 



Joined: 20 May 2020
Posts: 17
cyborc wrote:
according to the service manual, this tv is hot chassis. so if you are planning to add rgb inputs to it, it must always be plugged into an isolation transformer going forward.

https://www.manualslib.com/manual/69976 ... e=4#manual


Sadly, I have no idea what this means. What does hot chassis mean? Are you saying that I should:

  • discharge this TV with the screwdriver-touching-the-anode cap method (I've done this several times)
  • add RGB
  • plug the tv into an isolation transformer
  • plug the isolation transformer into the wall
  • enjoy?

If those are my steps, what isolation transformer do you recommend? There are a lot of different options for a lot of different prices. This TV was made in 2003.


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Sep 03, 2020 11:36 pm 


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Location: USA
zFleeman wrote:
cyborc wrote:
according to the service manual, this tv is hot chassis. so if you are planning to add rgb inputs to it, it must always be plugged into an isolation transformer going forward.

https://www.manualslib.com/manual/69976 ... e=4#manual


Sadly, I have no idea what this means. What does hot chassis mean? Are you saying that I should:

  • discharge this TV with the screwdriver-touching-the-anode cap method (I've done this several times)
  • add RGB
  • plug the tv into an isolation transformer
  • plug the isolation transformer into the wall
  • enjoy?

If those are my steps, what isolation transformer do you recommend? There are a lot of different options for a lot of different prices. This TV was made in 2003.


http://teaganm.cademo.com/images/other/ ... soxfmr.htm
That explains it better than I ever could.

I'm still learning about all this myself, but any information you read about arcade monitors and isolation transformers would pretty much apply to your Sanyo TV as well.


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 Post subject: Re: TV RGB mod thread
PostPosted: Fri Sep 04, 2020 12:18 am 



Joined: 20 May 2020
Posts: 17
Can you tell me where exactly that you saw this was a hot chassis? Nothing specifies that in the service manual that I can find.

Don’t worry though, I am not going to open this thing up without getting confirmation about how dangerous it is. Some guy on Reddit thinks it isn’t a hot chassis TV given that it is from 2003, and that it’s plug has the bulbous prong so it only fits in the electrical socket one way.

Or can somebody give a second opinion?


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 Post subject: Re: TV RGB mod thread
PostPosted: Fri Sep 04, 2020 10:55 am 



Joined: 02 Feb 2005
Posts: 344
zFleeman wrote:
Or can somebody give a second opinion?


Of course it's not a hot chassis. It's the usual modern design with switching power supply that provides isolation from the mains. Note on page 30 the different ground symbols on the two sides of the switching transformer: pin 3 = hot ground, pin 16 = cold ground. Only if your servicing the hot side of the PSU (the area within the thick line) you need to use an isolation transformer (or disconnect the ground of the testing device, oscilloscope, etc.).


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 Post subject: Re: TV RGB mod thread
PostPosted: Fri Sep 04, 2020 2:14 pm 


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Location: bmore
zFleeman wrote:
I had the unfortunate realization that the current grounding resistors and inline resistors are surface mount. I'm really really not looking forward to messing with such tiny parts



Probing surface mount stuff is generally easier to me; you can usually do everything from the same side of the board, so tracing it out in your head is easier. You can replace the surface mount stuff with through-hole when you have to do so.
The main thing is that you respect the values. I am also in the habit of using the same type of component (ceramic for ceramic, etc) because there are situations where it's generally necessary for one reason or another.

To use a through-hole component, you can bend the legs over to make little flat feet and then you solder the feet to pads. Using a small tip helps, but it's easier that dicking around with surface mount if you don't have the experience, and it's less risky. It's possible to melt too much solder underneath of a surface mount cap and bridge the pads together if you're not careful.


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